How to Change a YouTube Thumbnail on Desktop and Mobile

YouTube notes that thumbnail changes can take time to appear across the platform, so do not assume the save failed because every surface has not updated instantly.

YouTube Studio App

Main YouTube App

YouTube also documents a mobile route through Your videos: open the video's menu, choose Edit, then Edit thumbnail, select the image, and save.

• Recommended resolution: 3840 × 2160 pixels.
• Minimum width: 640 pixels.
• Recommended aspect ratio for normal videos: 16:9.
• Common supported image formats include JPG, GIF, and PNG.
• Desktop upload limit: currently 50 MB for video thumbnails.
• Mobile upload limit: currently 2 MB for video thumbnails.
• The account must be verified to upload custom thumbnails.

These requirements can change, so YouTube Help should remain the source of truth rather than old thumbnail templates that still cite 1280 × 720 and a universal 2 MB limit.

YouTube says you cannot upload a custom thumbnail for Shorts in the same way you can for long-form videos. You can select a frame from the Short for certain surfaces, and once that frame is selected, YouTube currently says it cannot be changed after upload.

Vertical videos may also use auto-generated crops on some mobile discovery surfaces even when a 16:9 custom image exists elsewhere.

Use YouTube Studio to investigate the video in context. A lower CTR than your comparable videos can justify testing packaging, but traffic source, topic breadth, impression expansion, and audience familiarity all affect CTR.

• The image no longer represents the video's strongest or clearest angle.
• The subject is difficult to identify at feed size.
• The title and thumbnail repeat each other instead of working together.
• YouTube Studio shows enough impressions to make packaging worth investigating.
• You have a genuinely different visual idea to test rather than a tiny cosmetic change.

You do not have to change the title whenever you change the thumbnail. You should, however, review the pair because a new visual angle can create a mismatch with the old wording.

TitleGen can generate several Niche-Locked title directions around the same video topic. It does not score predicted CTR or replace YouTube Studio testing.

After a change, watch impressions, CTR by traffic source, views, average view duration, and retention. Compare similar periods when possible, but remember that audience and traffic mix may also change over time.

Where available, YouTube Studio's native A/B testing can provide a cleaner way to compare title and thumbnail variations than manually switching assets on different days.